Inbred corn line G2202

ABSTRACT

Broadly this invention provides an invention which is inbred corn line G2202. The methods for producing a corn plant by crossing the inbred line G2202 are also encompassed by the invention. Additionally, the invention relates to the various parts of inbred G2202 including culturable cells. This invention relates to hybrid corn seeds and plants produced by crossing the inbred line G2202 with at least one other corn line.

REFERENCE TO RELATED APPLICATION

This is a continuation of prior application Ser. No. 10/097,451, filedMar. 13, 2002, and issued U.S. Pat. No. 6,818,812.

FIELD OF THE INVENTION

This invention is in the field of corn breeding, specifically relatingto an inbred corn line designated G2202. This invention also is in thefield of hybrid maize production employing the present inbred.

BACKGROUND OF THE INVENTION

The original maize plant was indigenous to the Western Hemisphere. Theplants were weedlike and only through the efforts of early breeders werecultivated crop species developed. The crop cultivated by earlybreeders, like the crop today, could be wind pollinated. The physicaltraits of maize are such that wind pollination results inself-pollination or cross-pollination between plants. Each plant has aseparate male and female flower that contributes to pollination, thetassel and ear, respectively. Natural pollination occurs when windtransfers pollen from tassel to the silks on the corn ears. This type ofpollination has contributed to the wide variation of maize varietiespresent in the Western Hemisphere.

The development of a planned breeding program for maize only occurred inthe last century. A large part of the development of the maize productinto a profitable agricultural crop was due to the work done by landgrant colleges. Originally, maize was an open pollinated variety havingheterogeneous genotypes. The maize farmer selected uniform ears from theyield of these genotypes and preserved them for planting the nextseason. The result was a field of maize plants that were segregating fora variety of traits. This type of maize selection led to, at most,incremental increases in seed yield.

Large increases in seed yield were due to the work done by land grantcolleges that resulted in the development of numerous hybrid cornvarieties in planned breeding programs. Hybrids were developed byselecting corn lines and selfing these lines for several generations todevelop homozygous pure inbred lines. One selected inbred line wascrossed with another selected inbred line to produce hybrid progeny(F1). The resulting hybrids, due to heterosis, are robust and vigorousplants. Inbreds on the other hand are mostly homozygous. Thishomozygosity renders the inbred lines less vigorous. Inbred seed can bedifficult to produce since the inbreeding process in corn linesdecreases the vigor. However, when two inbred lines are crossed, thehybrid plant evidences greatly increased vigor and seed yield comparedto open pollinated, segregating maize plants. An important consequenceof the homozygosity and the homogeneity of the inbred maize lines isthat all hybrid seed produced from any cross of two such elite lineswill be the same hybrid seed and make the same hybrid plant. Thus theuse of inbreds makes hybrid seed which can be reproduced readily. Thehybrid plant in contrast does not produce hybrid seed that is readilyreproducible. The seed on a hybrid plant is segregating for traits.

The ultimate objective of the commercial maize seed companies is toproduce high yielding, agronomically sound plants that perform well incertain regions or areas of the Corn Belt. To produce these types ofhybrids, the companies must develop inbreds, which carry needed traitsinto the hybrid combination. Hybrids are not often uniformly adapted forthe entire Corn Belt, but most often are specifically adapted forregions of the Corn Belt. Northern regions of the Corn Belt requireshorter season hybrids than do southern regions of the Corn Belt.Hybrids that grow well in Colorado and Nebraska soils may not flourishin richer Illinois and Iowa soil. Thus, a variety of major agronomictraits are important in hybrid combination for the various Corn Beltregions, and have an impact on hybrid performance.

Inbred line development and hybrid testing have been emphasized in thepast half-century in commercial maize production as a means to increasehybrid performance. Inbred development is usually done by pedigreeselection. Pedigree selection can be selection in an F₂ populationproduced from a planned cross of two genotypes (often elite inbredlines), or selection of progeny of synthetic varieties, open pollinated,composite, or backcrossed populations. This type of selection iseffective for highly inheritable traits, but other traits, for example,yield requires replicated test crosses at a variety of stages foraccurate selection.

Maize breeders select for a variety of traits in inbreds that impacthybrid performance along with selecting for acceptable parental traits.Such traits include: yield potential in hybrid combination; dry down;maturity; grain moisture at harvest; greensnap; resistance to rootlodging; resistance to stalk lodging; grain quality; disease and insectresistance; ear and plant height. Additionally, Hybrid performance willdiffer in different soil types such as low levels of organic matter,clay, sand, black, high pH, low pH; or in different environments such aswet environments, drought environments, and no tillage conditions. Thesetraits appear to be governed by a complex genetic system that makesselection and breeding of an inbred line extremely difficult. Even if aninbred in hybrid combination has excellent yield (a desiredcharacteristic), it may not be useful because it fails to haveacceptable parental traits such as seed yield, seed size, pollenproduction, good silks, plant height, etc.

To illustrate the difficulty of breeding and developing inbred lines,the following example is given. Two inbreds compared for similarity of29 traits differed significantly for 18 traits between the two lines. If18 simply inherited single gene traits were polymorphic with genefrequencies of 0.5 in the parental lines, and assuming independentsegregation (as would essentially be the case if each trait resided on adifferent chromosome arm), then the specific combination of these traitsas embodied in an inbred would only be expected to become fixed at arate of one in 262,144 possible homozygous genetic combinations.Selection of the specific inbred combination is also influenced by thespecific selection environment on many of these 18 traits which makesthe probability of obtaining this one inbred even more remote. Inaddition, most traits in the corn genome are regrettably not singledominant genes but are multi-genetic with additive gene action notdominant gene action. Thus, the general procedure of producing a nonsegregating F₁ generation and self pollinating to produce a F₂generation that segregates for traits and selecting progeny with thevisual traits desired does not easily lead to a useful inbred. Greatcare and breeder expertise must be used in selection of breedingmaterial to continue to increase yield and the agronomics of inbreds andresultant commercial hybrids.

Certain regions of the Corn Belt have specific difficulties that otherregions may not have. Thus the hybrids developed from the inbreds haveto have traits that overcome or at least minimize these regional growingproblems. Examples of these problems include in the eastern corn beltGray Leaf Spot, in the north cool temperatures during seedlingemergence, in the Nebraska region CLN (corn Lethal necrosis and in thewest soil that has excessively high pH levels. The industry oftentargets inbreds that address these issues specifically forming nicheproducts. However, the aim of most large seed producers is to provide anumber of traits to each inbred so that the corresponding hybrid canuseful in broader regions of the Corn Belt. The new biotechnologytechniques such as Microsatellites, RFLPs, RAPDs and the like haveprovided breeders with additional tools to accomplish these goals.

SUMMARY OF THE INVENTION

The present invention relates to an inbred corn line G2202.Specifically, this invention relates to plants and seeds of this line.Additionally, this relates to a method of producing from this inbred,hybrid seed corn and hybrid plants with seeds from such hybrid seed.More particularly, this invention relates to the unique combination oftraits that combine in corn line G2202.

Generally then, broadly the present invention includes an inbred cornseed designated G2202. This seed produces a corn plant.

The invention also includes the tissue culture of regenerable cells ofG2202 wherein the cells of the tissue culture regenerates plants capableof expressing the genotype of G2202. The tissue culture is selected fromthe group consisting of leaves, pollen, embryos, roots, root tips, guardcells, ovule, seeds, anthers, silk, flowers, kernels, ears, cobs, husksand stalks, cells and protoplasts thereof. The corn plant regeneratedfrom G2202 or any part thereof is included in the present invention. Thepresent invention includes regenerated corn plants that are capable ofexpressing G2202's genotype, phenotype or mutants or variants thereof.

The invention extends to hybrid seed produced by planting, inpollinating proximity which includes using preserved maize pollen asexplained in U.S. Pat. No. 5,596,838 to Greaves, seeds of corn inbredlines G2202 and another inbred line if preserved pollen is not used;cultivating corn plants resulting from said planting; preventing pollenproduction by the plants of one of the inbred lines if two are employed;allowing cross pollination to occur between said inbred lines; andharvesting seeds produced on plants of the selected inbred. The hybridseed produced by hybrid combination of plants of inbred corn seeddesignated G2202 and plants of another inbred line are apart of thepresent invention. This inventions scope covers hybrid plants and theplant parts including the grain and pollen grown from this hybrid seed.

The invention further includes a method of hybrid F1 production. A firstgeneration (F1) hybrid corn plant produced by the process of plantingseeds of corn inbred line G2202; cultivating corn plants resulting fromsaid planting; permitting pollen from another inbred line to crosspollinate inbred line G2202; harvesting seeds produced on plants of theinbred; and growing a harvested seed are part of the method of thisinvention.

Likewise included is a first generation (F1) hybrid corn plant producedby the process of planting seeds of corn inbred line G2202; cultivatingcorn plants resulting from said planting; permitting pollen from inbredline G2202 to cross pollinate another inbred line; harvesting seedsproduced on plants of the inbred; and growing a plant from such aharvested seed.

The inbred corn line G2202 and at least one transgenic gene adapted togive G2202 additional and/or altered phenotypic traits are within thescope of the invention. Such transgenes are usually associated withregulatory elements (promoters, enhancers, terminators and the like).Presently, trangenes provide the invention with traits such as insectresistance, herbicide resistance, disease resistance increased ordeceased starch or sugars or oils, increased or decreased life cycle orother altered trait.

The present invention includes inbred corn line G2202 and at least onetransgenic gene adapted to give G2202 modified starch traits.Furthermore this invention includes the inbred corn line G2202 and atleast one mutant gene adapted to give modified starch, acid or oiltraits. The present invention includes the inbred corn line G2202 and atleast one transgenic gene selected from the group consisting of:bacillus thuringiensis, the bar or pat gene encoding Phosphinothricinacetyl Transferase, Gdha gene, EPSP synthase gene, low phytic acidproducing gene, and zein. The inbred corn line G2202 and at least onetransgenic gene useful as a selectable marker or a screenable marker arecovered by the present invention.

A tissue culture of the regenerable cells of hybrid plants produced withuse of G2202 genetic material is covered by this invention. A tissueculture of the regenerable cells of the corn plant produced by themethod described above are also included.

Definitions

In the description and examples, which follow, a number of terms areused. In order to provide a clear and consistent understanding of thespecifications and claims, including the scope to be given such terms,the following definitions are provided.

BL MOIST

The moisture percentage of the grain at black layer, i.e., when 50% ofthe plants per plot have reached physiological maturity.

COLD GERM

Cold Germ is a measurement of seed germination under cold soilconditions. Data is reported as percent of seed germinating.

ECB

European corn borer is a maize eating insect. ECBI is the first broodgeneration of European corn borers. ECBII is the second generation ofEuropean corn borers. ECB1 is a rating of leaf damage. The ECBII (ECB2)rating is based upon tunneling. For all Entomology ratings, the highernumber is best (1=little or no resistance, 9=highly resistant). Thescale is slightly different for Ear Rating, which is taken on a 1–4basis. This is a rating of corn borer feeding on the ear. A 1 representsfeeding over the entire ear, while a 4 represents no observable feedingon the ear.EMERGE (EMG)The number of emerged plants per plot (planted at the same seedlingrate) collected when plants have two fully developed leaves.GIThis is a selection index that provides a single quantitative measure ofthe worth of a hybrid based on four traits. FI is a very similar indexwhich weights yield less than GI. In GI yield is the primary traitcontributing to index values. The GI value is calculated by combiningstalk lodging, root lodging, yield and dropped ears according to theattached mathematical formula:GI=100+0.5(YLD)−0.9(% STALK LODGE)−0.9(% ROOT LODGE)−2.7(% DROPPED EAR)GLSGray Leaf Spot (Cercospora Zeae) disease rating. This is rated on a 1–9scale with a “1” being very susceptible, and a “9” being veryresistant.*GWGross' Wilt (Corynebacterium nebraskense). This is rated on a 1–9 scalewith a “1” being very susceptible, and a “9” being very resistant.*HEATP10The number of Growing Degree Units (GDU's) or heat units required for aninbred line or hybrid to have approximately 10 percent of the plantsshedding pollen. This trait is measured from the time of planting.Growing Degree Units are calculated by the Barger Method where the GDU'sfor a 24 hour period are:

${GDU} = {\frac{\left( {{{Max}\mspace{14mu}{Temp}\mspace{14mu}\left( {{^\circ}\mspace{14mu}{F.}} \right)} + {{Min}\mspace{14mu}{Temp}\mspace{14mu}\left( {{^\circ}\mspace{14mu}{F.}} \right)}} \right)}{2} - 50}$The highest maximum temperature used is 86° F. and the lowest minimumtemperature used is 50° F. For each inbred or hybrid it takes a certainnumber of GDU's to reach various stages of plant development.HEATBLThe number of GDU's after planting when approximately 50 percent of theinbred or hybrid plants in a plot have grain that has reachedphysiological maturity (black layer).HEATPEEKThe number of GDU's after planting of an inbred when approximately 50percent of the plants show visible tassel extension.HEATP50 or HTP50The number of GDU's required for an inbred or hybrid to haveapproximately 50 percent of the plants shedding pollen. Growing DegreeUnits are calculated by the Barger Method as shown in the HEATP10definition.HEATP90The number of GDU's accumulated from planting when the last 100 percentof plants in an inbred or hybrid are still shedding enough viable pollenfor pollination to occur. Growing Degree Units are calculated by theBarger Method as shown in the HEATP10 definition.HEATS10The number of GDU's required for an inbred or hybrid to haveapproximately 10 percent of the plants with silk emergence of at least0.5 inches. Growing Degree Units are calculated by the Barger Method asshown in the HEATP10 definition.HEATS50 or HTS50The number of GDU's required for an inbred or hybrid to haveapproximately 50 percent of the plants with silk emergence of at least0.5 inches. Growing Degree Units are calculated by the Barger Method asshown in the HEATP10 definition.HEATS90The number of GDU's required for an inbred or hybrid to haveapproximately 90 percent of the plants with silk emergence of at least0.5 inches. Growing Degree Units are calculated by the Barger Method asshown in the HEATP10 definition.MDMV_(A)Maize Dwarf Mosaic Virus strain A. The corn is rated on a 1–9 scale witha “1” being very susceptible, and a “9” being very resistant.*MDMV_(B)Maize Dwarf Mosaic Virus strain B. This is rated on a 1–9 scale with a“1” being very susceptible and a “9” being very resistant.*MOISTUREThe average percentage grain moisture of an inbred or hybrid at harvesttime.NLBNorthern Leaf Blight (Exserohilum turcicum) disease rating. This israted on a 1–9 scale with a “1” being very susceptible, and a “9” beingvery resistant.*PCT TILLER or TILLER RATINGThe total number of tillers per plot divided by the total number ofplants per plot.PLANTThis term includes plant cells, plant protoplasts, plant cell tissuecultures from which corn plants can be regenerated, plant calli, plantclumps, and plant cells that are intact in plants or parts of plants,such as embryos, pollen, flowers, kernels, ears, cobs, leaves, husks,stalks, roots, root tips, anthers, silk and the like., and this termalso includes any transgenic DNA or (RNA) or portion thereof that havebeen introduced into the plant by whatever method.PLANT HEIGHT (PLTHT) (PHT)The distance in centimeters from ground level to the base of the tasselpeduncle.PLANT INTEGRITY (PLTINT) or (INT)The level of plant integrity on a scale of 1–9 with 9 evidencing thetrait most strongly: 1–2.9 ratings are low plant integrity, 3–5.9ratings are intermediate plant integrity, and 6–9 ratings are stronglyevidencing plant integrity.POPULATION (POP)The plant population.RMPredicted relative maturity based on the moisture percentage of thegrain at harvest. This rating is based on known set of checks andutilizes standard linear regression analyses and is referred to as theMinnesota Relative Maturity Rating System.SHEDThe volume of pollen shed by the male flower rated on a 1–5 scale wherea “1” is a very light pollen shedder, a “2.5” is a moderate shedder, anda “5” is a very heavy shedder.SLBSouthern Leaf Blight (Bipolaris maydis) disease rating. This is rated ona 1–9 scale with a “1” being very susceptible, and a “9” being veryresistant.*STAYGREEN (SGN)The level of staygreen of the plant on a scale of 1–9 with 9 evidencingthe trait most strongly: 1–2.9 ratings are low staygreen, 3–5.9 ratingsare intermediate staygreen, and 6–9 ratings are strongly evidencingstaygreen.TWTThe measure of the weight of grain in pounds for a one bushel volumeadjusted for percent grain moisture.VIGOR (VIG)Visual rating of 1 to 9 made 2–3 weeks post-emergence where a “1”indicates very poor early plant development, and a “9” indicatessuperior plant development.WARM GERMA measurement of seed germination under ideal (warm, moist) conditions.Data is reported as percent of seeds germinating.YIELD (YLD)Actual yield of grain at harvest adjusted to 15.5% moisture.Measurements are reported in bushels per acre.% DROPPED EARS (DE)The number of plants per plot, which dropped their primary ear, dividedby the total number of plants per plot.% ROOT LODGE (RL)Percentage of plants per plot leaning more that 30 degrees from verticaldivided by total plants per plot.% STALK LODGE (SL)Percentage of plants per plot with the stalk broken below the primaryear node divided by the total plants per plot.

-   -   Resistant—on a scale of 1–9 with 9 evidencing the trait most        strongly: 1–2.9 ratings are susceptible, 3–5.9 ratings are        intermediate, and 6–9 ratings are resistant.

DETAILED DESCRIPTION OF THE INVENTION

G2202 can be used as a male line or as a female line, although this lineis usually in the position of male. The line has good emergence. Inhybrid combination this line yields nice 108 day hybrids. The inbredcarries a distinct tolerance to corn rootworm.

The inbred has shown uniformity and stability within the limits ofenvironmental influence for all the traits as described in the VarietyDescription Information (Table 1) that follows.

The inbred has been self-pollinated for a sufficient number ofgenerations to give inbred uniformity. During plant selection in eachgeneration, the uniformity of plant type was selected to ensurehomozygosity and phenotypic stability. The line has been increased inisolated farmland environments with data on uniformity and agronomictraits being observed to assure uniformity and stability. No varianttraits have been observed or are expected in G2202.

The best method of producing the invention, G2202 which is substantiallyhomozygous, is by planting the seed of G2202 which is substantiallyhomozygous and self-pollinating or sib pollinating the resultant plantin an isolated environment, and harvesting the resultant seed.

TABLE 1 G2202 VARIETY DESCRIPTION INFORMATION #1 Type: Dent #2 RegionBest Adapted: Broadly adapted - Central, Eastern regions of the CornBelt. This inbred has RM of 107–109 in hybrid combinations. #3 PlantTraits Plant Height 76 in. Ear Height 33 in. Tillers (Rating)  5 LeafColor DARK GREEN Brace Root Color GREEN/RED Silk Color YELLOW Shoots atFlowering BALD #4 Tassel Traits Glume Color GREEN Glume Ring ColorOTHER/ABSENT Anther Color YELLOW #5 Ear and Kernel Traits Cob Color REDKernel Crown Color YELLOW #6 Disease Resistance In Inbred Gray Leaf Spot= 7.2 #7 Insect Resistance In Inbred ECB1 = 4.25000 ECB2 = 6.65638 Earrate = 2.4375 #8 The comparable inbred to G2202 is ZS4199, an inbredhaving a number of similarities. ZS4199 is an inbred which has been oris presently in commercial hybrids that are in a similar region ofadaptation as most of the hybrids formed with G2202.

The Munsell code is a reference book of color, which is known and usedin the industry and by persons with ordinary skill in the art of plantbreeding.

The purity and homozygosity of inbred G2202 is constantly being trackedusing isozyme genotypes as shown in Table 2.

Isozyme Genotypes for G2202

Isozyme data were generated for inbred corn line G2202 according toprocedures known and published in the art. The data in Table 2 gives theelectrophoresis data on G2202 as compared to its two parents.

TABLE 2 ELECTROPHORESIS RESULTS FOR G2202 INBRED ACP1 ACP4 ADH MDH1 MDH2PGD1 PGD2 PHI PGM IDH G2202 33 0 22 22 22 11 11 22 22 22Inbred and Hybrid Performance of G2202

The traits and characteristics of inbred corn line G2202 are listed tocompare with other inbreds and/or in hybrid combinations. The G2202 datashows the characteristics and traits of importance, giving a snapshot ofG2202 in these specific environments.

Table 3A shows a comparison between G2202 and a comparable inbredZS4199. G2202 has better seedling emergence than does inbred ZS4199. Thetwo inbreds show significant differences in ear height, plant height.Across all heat measurements for pollination G2202 shows pollen shedacross 223 heat units and ZS4199 shows pollen shed across less heatunits, only 169 heat units. G2202 does evidence significantly loweryield and moisture at harvest than does ZS4199 G2202 reaches heat peekwith significantly less heat units than does ZS4199.

TABLE 3A PAIRED INBRED COMPARISON DATA EAR PLANT HEAT YEAR INBRED YIELDMOISTURE HEIGHT HEIGHT EMERGE PEEK HEATP10 HEATP50 OVERALL G2202 58.311.6 84.9 195.7 87.8 1362.8 1424.9 1462 ZS4199 81.2 10.7 72.9 170.2 82.51398.1 1455.3 1493.2 # EXPTS 16 16 8 8 16 14 14 14 DIFF 22.9 0.9 12.125.6 5.3 35.3 30.4 31.2 PROB 0.000*** 0.033** 0.002*** 0.001*** 0.008***0.026** 0.014** 0.005*** % LRG MED % LRG MED % LRG YEAR INBRED HEATP90HEATS10 HEATS50 HEATS90 FLAT RND PLATELESS OVERALL G2202 1648.4 1457.61498.8 1552.2 11.4 37 40.2 ZS4199 1624.1 1469.1 1508.6 1545.7 33.7 30.917.7 # EXPTS 8 14 14 8 15 15 15 DIFF 24.3 11.5 9.8 6.5 22.3 6.2 22.5PROB 0.208 0.212 0.273 0.566 0.000*** 0.008*** 0.000*** % SML % SML %SML COLD WARM YEAR INBRED MED FLAT MED RND PLATELESS % CULL SHED GERMGERM OVERALL G2202 0.7 6.5 0.8 3.2 3.2 80 92.6 ZS4199 3.8 11.2 1.4 0.9 485.4 98.1 # EXPTS 15 15 15 15 12 10 10 DIFF 3.2 4.7 0.6 2.3 0.8 5.4 5.5PROB 0.000*** 0.000*** 0.007*** 0.000*** 0.025** 0.426 0.012** *.05 <PROB <= .10 **.01 < PROB <= .05 ***.00 < PROB <= .01

TABLE 3B PAIRED HYBRID COMPARISON DATA % ROOT % STALK % DROPPED TESTYEAR HYBRID LODGE LODGE EARS WEIGHT MOISTURE YIELD GI Y_M FI OVERALL(CI/G2202)IT 2.5 4.1 0.1 54.9 20.8 176.4 182.1 8.8 134.2 85901T 3.3 3.50 54.5 19.8 170.9 179.2 9 133.7 # EXPTS 242 242 242 241 242 242 242 242242 DIFF 0.9 0.5 0.1 0.3 1 5.5 2.9 0.2 0.5 PROB 0.084* 0.085* 0.006***0.001*** 0.000*** 0.000*** 0.001*** 0.010** 0.535 *.05 < PROB <= .10**.01 < PROB <= .05 ***.00 < PROB <= .01

Table 3B shows the Inbred G2202 in hybrid combination with a commoninbred and another hybrid combination that includes the same commoninbred and another inbred. Both of the common hybrids carry the IT(imazethapyr tolerance trait). When in these hybrid combinations thepresent inbred carries a significantly heavier test weight and adistinctively significant difference in moisture levels. The yieldlevels of the present invention in hybrid combination are significantlyhigher than the levels of the comparison hybrid.

Table 4 shows the GCA (general combining ability) estimates of G2202compared with the GCA estimates of the other inbreds. The estimates showthe number of experiment/location combinations in which the specifichybrid combination occurs weights the general combining ability. Theinterpretation of the data for all traits is that a positive comparisonis a practical advantage. A negative comparison is a practicaldisadvantage. The general combining ability of an inbred is clearlyevidenced by the results of the general combining ability estimates.This data compares the inbred parent in a number of hybrid combinationsto a group of “checks”. The check data is from other companies' hybrids,and Garst Seed's commercial products and pre-commercial hybrids, whichwere grown in the same sets and locations.

TABLE 4 N FI Y/M GI YLD MST % SL % RL % DE TWT POP RM G2202 XR = 884 1.00.2 0.3 1.1 0.3 −0.5 0.3 0.0 0.4 −159 107 ZS4199 XR = 9704 1.4 0.4 −0.6−1.2 0.9 −0.2 0.0 0.0 0.1 −23 106 FI = 100 + 0.5 (Yld) −2.3 (MST) −0.9(% SL) −0.9 (% RL) −2.7 ( % DE) POP = plants per acre RM = The MinnesotaRelative Maturity XR = GCA Estimate weighted by Experiment

Table 4 shows G2202 in XR crossed to different inbreds to form numeroushybrid combinations. G2202 in hybrid combination shows an excellentadvantage for yield compared to the commercial checks and the company'scommercial inbreds in hybrid combination. G2202 has a positive ratingfor most of the agronomic traits except to resistance to stalk lodging.In a number of categories the present invention surpasses the ZS4199line. The present inventions advantage in yield is excellent as is thetestweight advantage which is carried into the combinations.

TABLE 5A YIELD RESPONSE Research Plots HYBRID YIELD G2202/Inbred X 83107 132 156 181 205 Environment 75 100 125 150 175 200 Error: 12.3 #Plots 265

TABLE 5B YIELD RESPONSE Research Plots HYBRID YIELD ZS4199/Inbred X 81105 128 151 175 198 Environment 75 100 125 150 175 200 Error: 14.3 #Plots 2347

Table 5A shows the yield response of G2202 in hybrid combination incomparison with the plants in the environment around it at the samelocation. The data for the present inbred is showing consistently betterresults than the data of the comparison hybrid. (These results arewithin the error margin.) G2202 in hybrid combination, is an inbred thatworks well by providing yields better than the environment or similar tothe environments. Its performance shows that this is a consistentyielding inbred regardless of the environment. Table 5b shows the datafrom a different hybrid (without the present invention) that was formedwith the same common inbred as that in the hybrid combination of Table5A. In both instances the hybrids carry the herbicide tolerant gene intothe combination. This comparison hybrid is still yielding wellparticularly in the low and mid environments but it is not carrying theyield potential into the hybrid as well as the hybrid combination of thepresent invention in the higher environments.

TABLE 6 PAIRED COMPARISIONS FOR AGRONOMIC DATA TWO HYBRIDS WITH A COMMONINBRED (Cl) # Estd Adv Emg Adv Vig Adv Sgn Adv Int Adv G2202/Cl 22 90.11.7 6.4 0.0 7.0 0.8 6.2 3.6 7.3 2.6 Cl/Inbred 22 88.5 6.4 6.2 2.6 4.7

The interpretation of the data for all traits is that a positivecomparison is a practical advantage. A negative comparison is apractical disadvantage. In this hybrid combination the inbred G2202carries its early stand advantage into the hybrid and additionally thehybrid with line G2202 carries excellent staygreen and plant integrity.

The foregoing is set forth by way of example and is not intended tolimit the scope of the invention.

This invention also is directed to methods for producing a corn plant bycrossing a first parent corn plant with a second parent corn plantwherein the first or second parent corn plant is an inbred corn plantfrom the line G2202. Further, both first and second parent corn plantscan come from the inbred corn line G2202. A variety of breeding methodscan be selected depending on the mode of reproduction, the trait, andthe condition of the germplasm. Thus, any such methods using the inbredcorn line G2202 are part of this invention: selfing, backcrosses, hybridproduction, crosses to populations, haploid by such old and knownmethods of using stock material that induces haploids and antherculturing and the like. Additionally, this maize can, within the scopeof the invention, contain: a mutant gene such as but not limited tosugary 1 or shrunken 1 or waxy or AE or imazethapyr tolerant (IT or IR™)mutant gene; or transgenic genes such as but not limited to insectresistant genes such as Bacillus thuringiensis (Cry genes), or herbicideresistant genes such as Pat gene or Bar gene, EPSP, or disease resistantgenes such as the Mosaic virus resistant gene, etc., or trait alteringgenes such as flowering genes, oil modifying genes, senescence genes andthe like.

Various culturing techniques known to those skilled in the art, such ashaploid, (stock six is a method that has been in use for twenty yearsand is well known to those with skill in the art), transformation, and ahost of other conventional and unconventional methods are within thescope of the invention. All plants and plant cells produced using theinbred corn line are within the scope of this invention. The termtransgenic plant refers to plants having genetic sequences, which areintroduced into the genome of a plant by a transformation method and theprogeny thereof. Transformation methods are means for integrating newgenetic coding sequences into the plant's genome by the incorporation ofthese sequences into a plant through man's assistance, but not bybreeding practices.

Though there are a large number of known methods to transform plants,certain types of plants are more amenable to transformation than areothers. Tobacco is a readily transformable plant. The basic steps oftransforming plants including monocots are known in the art. These stepsare concisely outlined in U.S. Pat. No. 5,484,956 “Fertile TransgenicZea mays Plants Comprising Heterologous DNA Encoding BacillusThuringiensis Endotoxin” issued Jan. 16, 1996 and U.S. Pat. No.5,489,520 “Process of Producing Fertile Zea mays Plants and ProgenyComprising a Gene Encoding Phosphinothricin Acetyl Transferase” issuedFeb. 6, 1996.

Plant cells such as maize can be transformed by a number of differenttechniques. Some of these techniques which have been reported on and areknown in the art include maize pollen transformation (See University ofToledo 1993 U.S. Pat. No. 5,177,010); Biolistic gun technology (See U.S.Pat. No. 5,484,956); Whiskers technology (See U.S. Pat. Nos. 5,464,765and 5,302,523); Electroporation; PEG on Maize; Agrobacterium (See 1996article on transformation of maize cells in Nature Biotechnology, Volume14, June 1996) along with numerous other methods which may have slightlylower efficiency rates. Some of these methods require specific types ofcells and other methods can be practiced on any number of cell types.

The use of pollen, cotyledons, meristems and ovum as the target issuecan eliminate the need for extensive tissue culture work. Generally,cells derived from meristematic tissue are useful. Zygotic embryos canalso be used. Additionally, the method of transformation of meristematiccells of cereal is also taught in the PCT application WO96/04392. Any ofthe various cell lines, tissues, plants and plant parts can and havebeen transformed by those having knowledge in the art. Methods ofpreparing callus or protoplasts from various plants are well known inthe art and specific methods are detailed in patents and references usedby those skilled in the art. Cultures can be initiated from most of theabove-identified tissue. The only true requirement of the transformingmaterial is that it can form a transformed plant. The transgenic genecan come from various non-plant genes (such as; bacteria, yeast,animals, and viruses) along with being from plants.

The DNA used for transformation of these plants clearly may be circular,linear, and double or single stranded. Usually, the DNA is in the formof a plasmid. The plasmid usually contains regulatory and/or targetingsequences which assists the expression of the gene in the plant. Themethods of forming plasmids for transformation are known in the art.Plasmid components can include such items as: leader sequences, transitpolypeptides, promoters, terminators, genes, introns, marker genes, etc.The structures of the gene orientations can be sense, antisense, partialantisense, or partial sense: multiple gene copies can be used.

The regulatory promoters employed can be constitutive such as CaMv35S(usually for dicots) and polyubiquitin for monocots or tissue specificpromoters such as CAB promoters, etc. The prior art includes but is notlimited to octopine synthase, nopaline synthase, CaMv19S, mannopinesynthase promoters. These regulatory sequences can be combined withintrons, terminators, enhancers, leader sequences and the like in thematerial used for transformation.

The isolated DNA is then transformed into the plant. Many dicots caneasily be transformed with Agrobacterium. Some monocots are moredifficult to transform. As previously noted, there are a number ofuseful transformation processes. The improvements in transformationtechnology are beginning to eliminate the need to regenerate plants fromcells. Since 1986, the transformation of pollen has been published andrecently the transformation of plant meristems has been published. Thetransformation of ovum, pollen, and seedlings meristem greatly reducethe difficulties associated with cell regeneration of different plantsor genotypes which a maize plant can present. Duncan, from at least 1985produced literature on plant regeneration from callus. Both inbred andhybrid callus have resulted in regenerated plants. Somatic embryogenesishas been performed on various maize tissues, which was once consideredunusable for this purpose. The prior art clearly teaches theregeneration of plants from various maize tissues.

The most common method of maize transformation is referred to as gunningor microprojectile bombardment though the other methods can be used. TheBiolistic process has small gold-coated particles coated with DNA shotinto the transformable material. Techniques for gunning DNA into cells,tissue, callus, embryos, and the like are well known in the prior art.

After the transformation of the plant material is complete, the nextstep is identifying the cells or material, which has been transformed.In some cases, a screenable marker is employed such as thebeta-glucuronidase gene of the uidA locus of E. coli. Then, thetransformed cells expressing the colored protein are selected for eitherregeneration or further use. In many cases, a selectable markeridentifies the transformed material. The putatively transformed materialis exposed to a toxic agent at varying concentrations. The cells nottransformed with the selectable marker, which provides resistance tothis toxic agent, die. Cells or tissues containing the resistantselectable marker generally proliferate. It has been noted that althoughselectable markers protect the cells from some of the toxic affects ofthe herbicide or antibiotic, the cells may still be slightly affected bythe toxic agent by having slower growth rates. If the transformedmaterial was cell lines then these lines are regenerated into plants.The cells' lines are treated to induce tissue differentiation. Methodsof regeneration of cellular maize material are well known in the art.

All plants and plant cells produced using inbred corn line G2202 arewithin the scope of this invention. The invention encompasses the inbredcorn line used in crosses with other, different, corn inbreds to produce(F1) corn hybrid seeds and hybrid plants. This invention includes cells,which upon growth and differentiation produce corn plants having thephysiological and morphological characteristics of the inbred lineG2202.

A deposit of at least 2500 seeds of this invention will be maintained byGarst Seed Company, 2369 330th Street, Slater, Iowa 50244. Access tothis deposit will be available during the pendency of this applicationto the Commissioner of Patents and Trademarks and persons determined bythe Commissioner to be entitled thereto upon request. All restrictionson availability to the public of such material will be removed uponissuance of a granted patent of this application by depositing at least2500 seeds of this invention at the American Type Culture Collection(ATCC), at 10801 University Boulevard, Manassas, Va. 20110. The date ofdeposit was May 17, 2004 and the seeds were tested and found to beviable on May 24, 2004. The ATCC accession number is PTA-5973. The ATCCdeposit will be maintained in that depository, which is a publicdepository, for a period of 30 years, or 5 years after the last request,or for the effective life of the patent, whichever is longer, and willbe replaced if it becomes nonviable during that period.

Additional public information on some ZS designations may be availablefrom the PVP Office, a division of the US Government.

Accordingly, the present invention has been described with some degreeof particularity directed to the preferred embodiment of the presentinvention. It should be appreciated, though, that the present inventionis defined by the following claims construed in light of the prior artso that modifications or changes may be made to the preferred embodimentof the present invention without departing from the inventive conceptscontained herein.

1. Hybrid seed produced by a method comprising the following steps: (a)planting seed of corn inbred line G2202, a representative sample of seedhave been deposited under the ATCC accession number PTA-5972, and seedof another corn inbred line; (b) cultivating corn plants resulting fromsaid planting; (c) allowing cross pollination to occur between plants ofsaid inbred lines; (d) harvesting the resultant seed.
 2. Hybrid seedproduced by crossing a plant of inbred corn line designated G2202, arepresentative sample of seed have been deposited under the ATCCaccession number PTA-5972, and a plant of another corn inbred line, andharvesting the resultant hybrid seed.
 3. A hybrid plant produced bygrowing the seed of claim
 2. 4. A first generation (F1) hybrid cornplant produced by the process of: (a) planting seed of corn inbred lineG2202, a representative sample of seed have been deposited under ATCCaccession number PTA-5972, and seed of another corn inbred line; (b)cultivating corn plants resulting from said planting; (c) allowingnatural cross-pollination to occur between the plants of said inbredlines; (d) harvesting the resultant seed; and (e) growing the harvestedseed to produce F1 hybrid plant.
 5. A tissue culture of regenerablecells produced from a corn plant produced by growing the seed ofclaim
 1. 6. A tissue culture of regenerable cells produced from a cornplant produced by growing the seed of claim
 2. 7. The plant according toclaim 3, including in the plant at least one transgene.
 8. The seedaccording to claim 1, including in the seed at least one transgene. 9.Hybrid seed comprising at least one transgene, said seed produced bycrossing the corn plant of claim 7 with a corn plant of another inbredline.
 10. The hybrid seed according to claim 2, wherein the seedcomprises at least one mutant gene selected from the group consistingof: sugary_(—)1 mutant gene, shrunken_(—)1 mutant gene, waxy mutantgene, amylase extender (AE) mutant gene, and imazephapyr tolerant (IT)mutant gene.
 11. A hybrid plant produced by growing the seed of claim10, wherein the plant comprises the mutant gene.